Poly (dimethyl siloxane)/poly (2-hydroxyethyl methacrylate) interpenetrating polymer network beads as potential capsules for biomedical use

Silicone hydrogels represent a series of novel materials designed for extensive applications especially in the biomedical field. In the current work, a method to obtain poly (dimethyl siloxane)/poly (2-hydroxyethyl methacrylate) (PDMS/PHEMA) interpenetrating polymer network (IPN) beads was developed. With further optimization, up to 43% PHEMA was incorporated into size controllable PDMS microspheres, offers an improved hydrophilicity and thus a reduced protein adsorption for long-term use. Furthermore, we found the PDMS/PHEMA IPN beads possess a hollow capsule-like structure, proposing their application as novel drug delivery vehicles. In vitro release studies have demonstrated two release patterns of these IPN beads for water-soluble drugs just by modulating the drug concentration, suggesting their possible applications in different delivery systems. (C) 2011 Elsevier B.V. All rights reserved.